Comparative Study of Under-Reamed and Conventional Piles Subjected to Horizontal Machine-Induced Vibration in Homogeneous Clay

The study of the dynamic behavior of under-reamed piles in cohesive soils subjected to machine-induced vibrations is still at an early stage of development. This study uses a three-dimensional finite element model to analyze the performance of under-reamed piles subjected to horizontal sinusoidal loading (15 to 40 Hz). The model captures time-dependent displacement responses at varying excitation frequencies. Key geometric parameters such as shaft diameter, embedment ratio, bulb to shaft diameter ratio, bulb inclination angle, and bulb placement depth are investigated to determine their influence on vibration response. Single and double-bulb under-reamed pile configurations are compared to assess dynamic performance. Additionally, the study compares under-reamed piles with conventional straight piles by analyzing the percentage amplitude reduction due to geometric modifications. Displacement contours and energy dissipation plots demonstrate the pile’s response during and after machine-induced vibrations. The findings contribute to a better understanding of the dynamic behavior of under-reamed piles.